Donald Trump on Monday defended hush money payments reported by his former lawyer a day after Democrats said the US president could face impeachment and jail time if the transactions are proven to be campaign finance violations.

Trump, in early morning tweets, said Democrats were wrongly targeting “a simple private transaction” after court filings last week drew renewed attention to six-figure payments by his personal lawyer to two women during the 2016 campaign so they would not discuss affairs with Trump, Reuters reported.

On Sunday, US Congressman Jerrold Nadler, who will lead the Judiciary Committee when Democrats take control of the House of Representatives next month, said if the payments were found to violate campaign finance laws it would be an impeachable offense.

His Democratic counterpart on the Intelligence Committee, Representative Adam Schiff, said Trump could be indicted and could “face the real prospect of jail time.”

Under US law, campaign contributions, defined as things of value given to a campaign to influence an election, must be disclosed. Such payments are also limited to $2,700 per person.

Trump earlier this year acknowledged repaying his former lawyer Michael Cohen for the $130,000 paid to adult film actress, Stephanie Clifford. He previously disputed knowing anything about the payments.

On Monday, the president again denied wrongdoing and shifted any blame on Cohen.

“There was NO COLLUSION. So now the Dems go to a simple private transaction, wrongly call it a campaign contribution, which it was not,” Trump tweeted. “But even if it was, it is only a CIVIL CASE, like Obama’s – but it was done correctly by a lawyer and there would not even be a fine. Lawyer’s liability if he made a mistake, not me.”

US prosecutors on Friday sought prison time for Cohen, Trump’s self-proclaimed “fixer,” for the payments directed by Trump as well as on charges of evading taxes and lying to Congress.

The case stemmed from a federal investigation into alleged Russian interference in the 2016 presidential election and possible collusion with Trump’s campaign. Russia has denied interfering and Trump said his campaign did not cooperate with Moscow.